irqchip/gic: Prepare for more than 16 PPIs

GICv3.1 allows up to 80 PPIs (16 legaci PPIs and 64 Extended PPIs),
meaning we can't just leave the old 16 hardcoded everywhere.

We also need to add the infrastructure to discover the number of PPIs
on a per redistributor basis, although we still pretend there is only
16 of them for now.

No functional change.
Signed-off-by: Marc Zyngier <maz@kernel.org>

drivers/irqchip/irq-gic-common.c

@@ -128,26 +128,31 @@ void gic_dist_config(void __iomem *base, int gic_irqs,
 		sync_access();
 }
 
-void gic_cpu_config(void __iomem *base, void (*sync_access)(void))
+void gic_cpu_config(void __iomem *base, int nr, void (*sync_access)(void))
 {
 	int i;
 
 	/*
 	 * Deal with the banked PPI and SGI interrupts - disable all
-	 * PPI interrupts, ensure all SGI interrupts are enabled.
-	 * Make sure everything is deactivated.
+	 * private interrupts. Make sure everything is deactivated.
 	 */
-	writel_relaxed(GICD_INT_EN_CLR_X32, base + GIC_DIST_ACTIVE_CLEAR);
-	writel_relaxed(GICD_INT_EN_CLR_PPI, base + GIC_DIST_ENABLE_CLEAR);
-	writel_relaxed(GICD_INT_EN_SET_SGI, base + GIC_DIST_ENABLE_SET);
+	for (i = 0; i < nr; i += 32) {
+		writel_relaxed(GICD_INT_EN_CLR_X32,
+			       base + GIC_DIST_ACTIVE_CLEAR + i / 8);
+		writel_relaxed(GICD_INT_EN_CLR_X32,
+			       base + GIC_DIST_ENABLE_CLEAR + i / 8);
+	}
 
 	/*
 	 * Set priority on PPI and SGI interrupts
 	 */
-	for (i = 0; i < 32; i += 4)
+	for (i = 0; i < nr; i += 4)
 		writel_relaxed(GICD_INT_DEF_PRI_X4,
 					base + GIC_DIST_PRI + i * 4 / 4);
 
+	/* Ensure all SGI interrupts are now enabled */
+	writel_relaxed(GICD_INT_EN_SET_SGI, base + GIC_DIST_ENABLE_SET);
+
 	if (sync_access)
 		sync_access();
 }

drivers/irqchip/irq-gic-common.h

@@ -22,7 +22,7 @@ int gic_configure_irq(unsigned int irq, unsigned int type,
                        void __iomem *base, void (*sync_access)(void));
 void gic_dist_config(void __iomem *base, int gic_irqs,
 		     void (*sync_access)(void));
-void gic_cpu_config(void __iomem *base, void (*sync_access)(void));
+void gic_cpu_config(void __iomem *base, int nr, void (*sync_access)(void));
 void gic_enable_quirks(u32 iidr, const struct gic_quirk *quirks,
 		void *data);
 void gic_enable_of_quirks(const struct device_node *np,

drivers/irqchip/irq-gic-v3.c

@@ -51,6 +51,7 @@ struct gic_chip_data {
 	u32			nr_redist_regions;
 	u64			flags;
 	bool			has_rss;
+	unsigned int		ppi_nr;
 	struct partition_desc	*ppi_descs[16];
 };
 
@@ -812,19 +813,24 @@ static int gic_populate_rdist(void)
 	return -ENODEV;
 }
 
-static int __gic_update_vlpi_properties(struct redist_region *region,
-					void __iomem *ptr)
+static int __gic_update_rdist_properties(struct redist_region *region,
+					 void __iomem *ptr)
 {
 	u64 typer = gic_read_typer(ptr + GICR_TYPER);
 	gic_data.rdists.has_vlpis &= !!(typer & GICR_TYPER_VLPIS);
 	gic_data.rdists.has_direct_lpi &= !!(typer & GICR_TYPER_DirectLPIS);
+	gic_data.ppi_nr = 16;
 
 	return 1;
 }
 
-static void gic_update_vlpi_properties(void)
+static void gic_update_rdist_properties(void)
 {
-	gic_iterate_rdists(__gic_update_vlpi_properties);
+	gic_data.ppi_nr = UINT_MAX;
+	gic_iterate_rdists(__gic_update_rdist_properties);
+	if (WARN_ON(gic_data.ppi_nr == UINT_MAX))
+		gic_data.ppi_nr = 0;
+	pr_info("%d PPIs implemented\n", gic_data.ppi_nr);
 	pr_info("%sVLPI support, %sdirect LPI support\n",
 		!gic_data.rdists.has_vlpis ? "no " : "",
 		!gic_data.rdists.has_direct_lpi ? "no " : "");
@@ -968,6 +974,7 @@ static int gic_dist_supports_lpis(void)
 static void gic_cpu_init(void)
 {
 	void __iomem *rbase;
+	int i;
 
 	/* Register ourselves with the rest of the world */
 	if (gic_populate_rdist())
@@ -978,9 +985,10 @@ static void gic_cpu_init(void)
 	rbase = gic_data_rdist_sgi_base();
 
 	/* Configure SGIs/PPIs as non-secure Group-1 */
-	writel_relaxed(~0, rbase + GICR_IGROUPR0);
+	for (i = 0; i < gic_data.ppi_nr + 16; i += 32)
+		writel_relaxed(~0, rbase + GICR_IGROUPR0 + i / 8);
 
-	gic_cpu_config(rbase, gic_redist_wait_for_rwp);
+	gic_cpu_config(rbase, gic_data.ppi_nr + 16, gic_redist_wait_for_rwp);
 
 	/* initialise system registers */
 	gic_cpu_sys_reg_init();
@@ -1449,7 +1457,7 @@ static int __init gic_init_bases(void __iomem *dist_base,
 
 	set_handle_irq(gic_handle_irq);
 
-	gic_update_vlpi_properties();
+	gic_update_rdist_properties();
 
 	gic_smp_init();
 	gic_dist_init();

drivers/irqchip/irq-gic.c

@@ -543,7 +543,7 @@ static int gic_cpu_init(struct gic_chip_data *gic)
 				gic_cpu_map[i] &= ~cpu_mask;
 	}
 
-	gic_cpu_config(dist_base, NULL);
+	gic_cpu_config(dist_base, 32, NULL);
 
 	writel_relaxed(GICC_INT_PRI_THRESHOLD, base + GIC_CPU_PRIMASK);
 	gic_cpu_if_up(gic);

drivers/irqchip/irq-hip04.c

@@ -273,7 +273,7 @@ static void hip04_irq_cpu_init(struct hip04_irq_data *intc)
 		if (i != cpu)
 			hip04_cpu_map[i] &= ~cpu_mask;
 
-	gic_cpu_config(dist_base, NULL);
+	gic_cpu_config(dist_base, 32, NULL);
 
 	writel_relaxed(0xf0, base + GIC_CPU_PRIMASK);
 	writel_relaxed(1, base + GIC_CPU_CTRL);